簡介
本文章介紹如何使用ceph為k8s提供動态申請pv的功能。ceph 提供底層存儲功能，cephfs方式支援k8s的pv的3種通路模式
ReadWriteOnce，ReadOnlyMany ，ReadWriteMany
，RBD支援
ReadWriteOnce，ReadOnlyMany
兩種模式
通路模式隻是能力描述，并不是強制執行的，對于沒有按pvc聲明的方式使用pv，存儲提供者應該負責通路時的運作錯誤。例如如果設定pvc的通路模式為
ReadOnlyMany
，pod挂載後依然可寫，如果需要真正的不可寫，申請pvc是需要指定
readOnly: true
參數
部署
部署k8s
centos7使用kubeadm安裝k8s-1.11版本部署ceph
centos7安裝ceph分布式存儲叢集在k8s叢集中配置使用ceph
使用Ceph RBD
使用kubeadm安裝叢集的額外配置
# 如果使用kubeadm部署的叢集需要這些額外的步驟 # 由于使用動态存儲時 controller-manager 需要使用 rbd 指令建立 image # 是以 controller-manager 需要使用 rbd 指令 # 由于官方controller-manager鏡像裡沒有rbd指令 # 如果沒使用如下方式會報錯無法成功建立pvc # 相關 issue https://github.com/kubernetes/kubernetes/issues/38923
cat >external-storage-rbd-provisioner.yaml<<EOF
apiVersion: v1
kind: ServiceAccount
metadata:
name: rbd-provisioner
namespace: kube-system
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: rbd-provisioner
rules:
- apiGroups: [""]
resources: ["persistentvolumes"]
verbs: ["get", "list", "watch", "create", "delete"]
- apiGroups: [""]
resources: ["persistentvolumeclaims"]
verbs: ["get", "list", "watch", "update"]
- apiGroups: ["storage.k8s.io"]
resources: ["storageclasses"]
verbs: ["get", "list", "watch"]
- apiGroups: [""]
resources: ["events"]
verbs: ["create", "update", "patch"]
- apiGroups: [""]
resources: ["endpoints"]
verbs: ["get", "list", "watch", "create", "update", "patch"]
- apiGroups: [""]
resources: ["services"]
resourceNames: ["kube-dns"]
verbs: ["list", "get"]
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: rbd-provisioner
subjects:
- kind: ServiceAccount
name: rbd-provisioner
namespace: kube-system
roleRef:
kind: ClusterRole
name: rbd-provisioner
apiGroup: rbac.authorization.k8s.io
---
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
name: rbd-provisioner
namespace: kube-system
rules:
- apiGroups: [""]
resources: ["secrets"]
verbs: ["get"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: rbd-provisioner
namespace: kube-system
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: rbd-provisioner
subjects:
- kind: ServiceAccount
name: rbd-provisioner
namespace: kube-system
---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: rbd-provisioner
namespace: kube-system
spec:
replicas: 1
strategy:
type: Recreate
template:
metadata:
labels:
app: rbd-provisioner
spec:
containers:
- name: rbd-provisioner
image: "quay.io/external_storage/rbd-provisioner:v2.0.0-k8s1.11"
env:
- name: PROVISIONER_NAME
value: ceph.com/rbd
serviceAccount: rbd-provisioner
EOF
kubectl apply -f external-storage-rbd-provisioner.yaml
# 檢視狀态 等待running之後 再進行後續的操作
kubectl get pod -n kube-system
複制代碼 配置 storageclass
# 在k8s叢集中所有節點安裝 ceph-common # 需要使用kubelet使用rdb指令map附加rbd建立的image
yum install -y ceph-common
# 建立 osd pool 在ceph的mon或者admin節點
ceph osd pool create kube 4096
ceph osd pool ls
# 建立k8s通路ceph的使用者 在ceph的mon或者admin節點
ceph auth get-or-create client.kube mon 'allow r' osd 'allow class-read object_prefix rbd_children, allow rwx pool=kube' -o ceph.client.kube.keyring
# 檢視key 在ceph的mon或者admin節點
ceph auth get-key client.admin
ceph auth get-key client.kube
# 建立 admin secret # CEPH_ADMIN_SECRET 替換為 client.admin 擷取到的key export CEPH_ADMIN_SECRET='AQBBAnRbSiSOFxAAEZXNMzYV6hsceccYLhzdWw=='
kubectl create secret generic ceph-secret --type="kubernetes.io/rbd" \
--from-literal=key=$CEPH_ADMIN_SECRET \
--namespace=kube-system
# 在 default 命名空間建立pvc用于通路ceph的 secret # CEPH_KUBE_SECRET 替換為 client.kube 擷取到的key export CEPH_KUBE_SECRET='AQBZK3VbTN/QOBAAIYi6CRLQcVevW5HM8lunOg=='
kubectl create secret generic ceph-user-secret --type="kubernetes.io/rbd" \
--from-literal=key=$CEPH_KUBE_SECRET \
--namespace=default
# 檢視 secret
kubectl get secret ceph-user-secret -o yaml
kubectl get secret ceph-secret -n kube-system -o yaml
# 配置 StorageClass # 如果使用kubeadm建立的叢集 provisioner 使用如下方式 # provisioner: ceph.com/rbd
cat >storageclass-ceph-rdb.yaml<<EOF
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
name: dynamic-ceph-rdb
provisioner: ceph.com/rbd
# provisioner: kubernetes.io/rbd
parameters:
monitors: 11.11.11.111:6789,11.11.11.112:6789,11.11.11.113:6789
adminId: admin
adminSecretName: ceph-secret
adminSecretNamespace: kube-system
pool: kube
userId: kube
userSecretName: ceph-user-secret
fsType: ext4
imageFormat: "2"
imageFeatures: "layering"
EOF
# 建立
kubectl apply -f storageclass-ceph-rdb.yaml
# 檢視
kubectl get sc
複制代碼 測試使用
# 建立pvc測試
cat >ceph-rdb-pvc-test.yaml<<EOF
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
name: ceph-rdb-claim
spec:
accessModes:
- ReadWriteOnce
storageClassName: dynamic-ceph-rdb
resources:
requests:
storage: 2Gi
EOF
kubectl apply -f ceph-rdb-pvc-test.yaml
# 檢視
kubectl get pvc
kubectl get pv
# 建立 nginx pod 挂載測試
cat >nginx-pod.yaml<<EOF
apiVersion: v1
kind: Pod
metadata:
name: nginx-pod1
labels:
name: nginx-pod1
spec:
containers:
- name: nginx-pod1
image: nginx:alpine
ports:
- name: web
containerPort: 80
volumeMounts:
- name: ceph-rdb
mountPath: /usr/share/nginx/html
volumes:
- name: ceph-rdb
persistentVolumeClaim:
claimName: ceph-rdb-claim
EOF
kubectl apply -f nginx-pod.yaml
# 檢視
kubectl get pods -o wide
# 修改檔案内容
kubectl exec -ti nginx-pod1 -- /bin/sh -c 'echo Hello World from Ceph RBD!!! > /usr/share/nginx/html/index.html' # 通路測試
POD_ID=$(kubectl get pods -o wide | grep nginx-pod1 | awk '{print $(NF-1)}')
curl http://$POD_ID # 清理
kubectl delete -f nginx-pod.yaml
kubectl delete -f ceph-rdb-pvc-test.yaml
複制代碼 使用 CephFS
linux核心需要4.10+，否則會出現無法正常使用的問題，詳細issue資訊 github.com/kubernetes-… centos7更新核心
在ceph叢集建立CephFS
# 如下操作在ceph的mon或者admin節點 # CephFS需要使用兩個Pool來分别存儲資料和中繼資料
ceph osd pool create fs_data 128
ceph osd pool create fs_metadata 128
ceph osd lspools
# 建立一個CephFS
ceph fs new cephfs fs_metadata fs_data
# 檢視
ceph fs ls
複制代碼 部署cephfs-provisioner
# 官方沒有cephfs動态卷支援 # 使用社群提供的cephfs-provisioner
cat >external-storage-cephfs-provisioner.yaml<<EOF
apiVersion: v1
kind: ServiceAccount
metadata:
name: cephfs-provisioner
namespace: kube-system
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: cephfs-provisioner
rules:
- apiGroups: [""]
resources: ["persistentvolumes"]
verbs: ["get", "list", "watch", "create", "delete"]
- apiGroups: [""]
resources: ["persistentvolumeclaims"]
verbs: ["get", "list", "watch", "update"]
- apiGroups: ["storage.k8s.io"]
resources: ["storageclasses"]
verbs: ["get", "list", "watch"]
- apiGroups: [""]
resources: ["events"]
verbs: ["create", "update", "patch"]
- apiGroups: [""]
resources: ["endpoints"]
verbs: ["get", "list", "watch", "create", "update", "patch"]
- apiGroups: [""]
resources: ["secrets"]
verbs: ["create", "get", "delete"]
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: cephfs-provisioner
subjects:
- kind: ServiceAccount
name: cephfs-provisioner
namespace: kube-system
roleRef:
kind: ClusterRole
name: cephfs-provisioner
apiGroup: rbac.authorization.k8s.io
---
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
name: cephfs-provisioner
namespace: kube-system
rules:
- apiGroups: [""]
resources: ["secrets"]
verbs: ["create", "get", "delete"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: cephfs-provisioner
namespace: kube-system
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: cephfs-provisioner
subjects:
- kind: ServiceAccount
name: cephfs-provisioner
namespace: kube-system
---
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: cephfs-provisioner
namespace: kube-system
spec:
replicas: 1
strategy:
type: Recreate
template:
metadata:
labels:
app: cephfs-provisioner
spec:
containers:
- name: cephfs-provisioner
image: "quay.io/external_storage/cephfs-provisioner:v2.0.0-k8s1.11"
env:
- name: PROVISIONER_NAME
value: ceph.com/cephfs
command:
- "/usr/local/bin/cephfs-provisioner"
args:
- "-id=cephfs-provisioner-1"
serviceAccount: cephfs-provisioner
EOF
kubectl apply -f external-storage-cephfs-provisioner.yaml
# 檢視狀态 等待running之後 再進行後續的操作
kubectl get pod -n kube-system
複制代碼 #####配置 storageclass
# 檢視key 在ceph的mon或者admin節點
ceph auth get-key client.admin
# 建立 admin secret # CEPH_ADMIN_SECRET 替換為 client.admin 擷取到的key # 如果在測試 ceph rbd 方式已經添加 可以略過此步驟 export CEPH_ADMIN_SECRET='AQBBAnRbSiSOFxAAEZXNMzYV6hsceccYLhzdWw=='
kubectl create secret generic ceph-secret --type="kubernetes.io/rbd" \
--from-literal=key=$CEPH_ADMIN_SECRET \
--namespace=kube-system
# 檢視 secret
kubectl get secret ceph-secret -n kube-system -o yaml
# 配置 StorageClass
cat >storageclass-cephfs.yaml<<EOF
kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
name: dynamic-cephfs
provisioner: ceph.com/cephfs
parameters:
monitors: 11.11.11.111:6789,11.11.11.112:6789,11.11.11.113:6789
adminId: admin
adminSecretName: ceph-secret
adminSecretNamespace: "kube-system"
claimRoot: /volumes/kubernetes
EOF
# 建立
kubectl apply -f storageclass-cephfs.yaml
# 檢視
kubectl get sc
複制代碼 # 建立pvc測試
cat >cephfs-pvc-test.yaml<<EOF
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
name: cephfs-claim
spec:
accessModes:
- ReadWriteOnce
storageClassName: dynamic-cephfs
resources:
requests:
storage: 2Gi
EOF
kubectl apply -f cephfs-pvc-test.yaml
# 檢視
kubectl get pvc
kubectl get pv
# 建立 nginx pod 挂載測試
cat >nginx-pod.yaml<<EOF
apiVersion: v1
kind: Pod
metadata:
name: nginx-pod1
labels:
name: nginx-pod1
spec:
containers:
- name: nginx-pod1
image: nginx:alpine
ports:
- name: web
containerPort: 80
volumeMounts:
- name: cephfs
mountPath: /usr/share/nginx/html
volumes:
- name: cephfs
persistentVolumeClaim:
claimName: cephfs-claim
EOF
kubectl apply -f nginx-pod.yaml
# 檢視
kubectl get pods -o wide
# 修改檔案内容
kubectl exec -ti nginx-pod1 -- /bin/sh -c 'echo Hello World from CephFS!!! > /usr/share/nginx/html/index.html' # 通路測試
POD_ID=$(kubectl get pods -o wide | grep nginx-pod1 | awk '{print $(NF-1)}')
curl http://$POD_ID # 清理
kubectl delete -f nginx-pod.yaml
kubectl delete -f cephfs-pvc-test.yaml 本文轉自掘金-
k8s使用ceph實作動态持久化存儲![DB2表壓縮功能[圖]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)